package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.Collections;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Slf4j
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Resource
    private ISeckillVoucherService seckillVoucherService;
    @Resource
    private RedisIdWorker redisIdWorker;
    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Resource
    private RedissonClient redissonClient;
    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    static {
        SECKILL_SCRIPT=new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }
    //阻塞队列
    private BlockingQueue<VoucherOrder> orderTask=new ArrayBlockingQueue<>(1024*1024);
    //获取线程池
    private static final ExecutorService SECKILL_ORDER_EXECUTOR= Executors.newSingleThreadExecutor();
    @PostConstruct
    private void init(){
       SECKILL_ORDER_EXECUTOR.submit(new VoucherOrderHandler());
    }

    //线程任务
     private class VoucherOrderHandler implements Runnable{

         @Override
         public void run() {
            while (true){

                try {
                    //1.获取队列中的订单信息
                    VoucherOrder voucherOrder = orderTask.take();
                    //2.创建订单
                    handleVoucherOrder(voucherOrder);
                } catch (Exception e) {
                    log.error("处理订单异常信息",e);
                }
            }
         }
     }

    private void handleVoucherOrder(VoucherOrder voucherOrder) {
      //1.获取用户
        Long userId = voucherOrder.getUserId();
        //2.创建锁对象
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        //3.获取锁
        boolean isLock = lock.tryLock();
        //4.判断是否获取成功
        if (!isLock){
            //获取锁失败，返回错误或重试
            log.error("不允许重复下单");
            return;
        }
        try {
            proxy.createVoucherOrder(voucherOrder);
        }finally {
            lock.unlock();
        }

    }
    IVoucherOrderService proxy;
    @Override
    public Result seckilVoucher(Long voucherId) {

        Long userId = UserHolder.getUser().getId();
        //1.执行luo脚本
        Long result = stringRedisTemplate.execute(
                SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(),
                userId.toString()
        );
        int r = result.intValue();
        //2.判断结果是否为0
         if (r!=0){
             //2.1不为0 代表没有购买资格
             return Result.fail(r==1?"库存不足":"不能重复下单");
         }
        //2.2为0 代表有购买资格 把下单信息保存到阻塞队列
        long orderId = redisIdWorker.nextId("order");
        //
        VoucherOrder voucherOrder=new VoucherOrder();
        //3.1订单id
        long oederId = redisIdWorker.nextId("order");
        voucherOrder.setId(oederId);
        //3.2用户id
        Long userId2 = UserHolder.getUser().getId();
        voucherOrder.setUserId(userId2);
        //3.3代金券id
        voucherOrder.setVoucherId(voucherId);
         //3,4放入阻塞队列
        orderTask.add(voucherOrder);
         //4.获取代理对象
         proxy =(IVoucherOrderService) AopContext.currentProxy();
        //5返回订单id
        return Result.ok(0);
    }
   // @Override
   /* public Result seckilVoucher(Long voucherId) {
        //1.查询优惠劵
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
        //2.判断秒杀是否开始
         if (voucher.getBeginTime().isAfter(LocalDateTime.now())){
             //开始时间在当前时间之后  1  2
             Result.ok("秒杀未开始");
         }
        //3.判断秒杀是否结束
         if (voucher.getEndTime().isBefore(LocalDateTime.now())){
             Result.fail("秒杀已经结束");
         }
        //4.判断库存是否充足
         if (voucher.getStock()<1){
             Result.fail("库存不足！");
         }
        //5.一人一单
        Long userId= UserHolder.getUser().getId();
       //创建锁对象
       // SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, stringRedisTemplate);
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        //获取锁
        boolean isLock = lock.tryLock();
        if (!isLock){
            //获取锁失败，返回错误
            return Result.fail("不允许重复下单");
        }
        //获取代理对象（事务）
        try {
            IVoucherOrderService proxy =(IVoucherOrderService) AopContext.currentProxy();
            return proxy.createVoucherOrder(voucherId);
        } finally {
            lock.unlock();
        }
    }*/
    @Transactional
    public void createVoucherOrder(VoucherOrder voucherOrder) {
        Long userId= voucherOrder.getUserId();
        Long voucherId = voucherOrder.getVoucherId();
        //5.1查询订单
        int count = query().eq("user_id", userId).eq("voucher_id", voucherId).count();
        //5.2判断是否存在
        if (count>0){
            //用户已经购买过了
           log.error("用户已经购买过一次了！");
           return;
        }
        //6.扣减库存
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock-1")
                .eq("voucher_id", voucherId)
                .gt("stock",0)
                .update();
        if (!success){
            //扣减失败
           log.error("扣减失败库存不足");
           return;
        }

        save(voucherOrder);

    }
}
